[tx_eggman]

Instead of using very expensive drillings in order to produce half a dozen million barrels of oil per day, it would be a better idea to save this oil.
Then, we could expect to see oil prices below $70.

Let me get this straight .. you're saying that not using very expensive drillings in order to produce half a dozen million barrels of oil per day ... which ipso facto reduces supply by half a dozen million barrels of oil per day ... would lower the cost of oil to below $70 per barrel..

You're either unclear about how supply and demand works or about simple math .. maybe both.

[Laurent.w]

As explained Javier Blas, Commodities Editor "Costs rise for ‘technological barrels’ of oil".
"Sanford C. Bernstein, the Wall Street research company, calls the rapid increase in production costs “the dark side of the golden age of shale”. In a recent analysis, it estimates that non-Opec marginal cost of production rose last year to $104.5 a barrel, up more than 13 per cent from $92.3 a barrel in 2011.
The big increase will have implications both for the market and oil companies, helping to put a floor to energy prices.
Sanford C. Bernstein estimates that the marginal cost of oil production has increased about 250 per cent over the last decade, rising from just under $30 a barrel in 2002 to a record of $104.5 a barrel last year."(Financial Times)

So, instead of using very expensive drillings in order to produce half a dozen million barrels of oil per day, we should save at least half a dozen million barrels of oil per day.
Then, the oil market would be as it was 10 years ago when oil was far less expensive, even during the war in iraq.